Now, to the high-stakes moment for general david petraeus, facing a new investigation into the sex scandal that's cost him the cia director's job. Petraeus will go behind closed doors on capitol hill today to testify about the deadly attack on the u.S. Consulate in benghazi. Abc's chief investigative correspondent, brian ross, is here with more on that. We're also learning more about the women at the center of this. Reporter: As best we know general petraeus is being called to answer questions about only what went wrong when four americans died in the terrorist attack in benghazi. He is expected to talk about security videos from the consulate and surveillance video from an unmanned drone that showed events in real-time. Petraeus will take the familiar walk this morning to a senate hearing room, knowing that the senators have agreed not to ask him about his extramarital affair, leaving that to others for you, including the inspector general of the cia. One question that has been answered in the case involved the so-called shirtless fbi agent, fred humphries, who started the investigation. "The seattle times" published this shirtless photo thursday. And as humphries had claimed, it appears to be more a joke than something sexually provocative. Other questions to be answered at some point involve how two of the women close to petraeus tried to use their connections to him. His mistress, paula broadwell gave a testimonial and demonstrated a machine gun for a company looking for military contracts. For an individual fighter, reducing weight is critical. Reporter: Watchdog groups say it was a brilliant move by the company. He knew he was friends with her. Reporter: And another friend of petraeus, tampa socialite, jill kelley, allegedly used the cia director's name in an effort this summer to broker a contract for a $4 billion emergency facility for senior officials of the south koreangovernment. This according to adam victor. Miss kelley made it clear to me that general petraeus put her in this position. That's why she had access to senior levels. They were doing a favor to general petraeus. Reporter: Victor said he broke off dealing with kelley after she asked for a commission that would come to $80 million. A spokesperson for jill kelley did not respond to questions asked by abc news. But a source close to the general said he had nothing whatsoever to do with a deal that jill kelley was trying to make. And he had asked her to stop throwing his name around. That explains a lot.

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